Systems approaches to scaling up: a systematic review and narrative synthesis of evidence for physical activity and other behavioural non-communicable disease risk factors

BACKGROUND

Non-communicable diseases (NCDs) are the leading causes of death worldwide. Systems approaches have potential for creating sustainable outcomes at scale but have rarely been used to support scale up in physical activity/nutrition promotion or NCD prevention more generally. This review aimed to: (i) synthesise evidence on the use of systems approaches in scaling up interventions targeting four behavioural risk factors for NCDs; and (ii) to explore how systems approaches have been conceptualised and used in intervention implementation and scale up.

METHOD

Seven electronic databases were searched for studies published 2016-2021. Eligible studies targeted at least one of four NCD behavioural risk factors (physical inactivity, tobacco use, alcohol consumption, diet), or described evaluation of an intervention planned for or scaled up. Studies were categorised as having a (i) high, (ii) moderate, or (iii) no use of a systems approach. A narrative synthesis of how systems approaches had been operationalised in scale up, following PRISMA guidelines.

RESULTS

Twenty-one intervention studies were included. Only 19% (n = 4) of interventions explicitly used systems thinking to inform intervention design, implementation and scale up (targeting all four risk factors n = 2, diet n = 1, tobacco use n = 1). Five studies ('high use') planned and implemented scale up with an explicit focus on relations between system elements and used system changes to drive impact at scale. Seven studies ('moderate use') considered systems elements impacting scale-up processes or outcomes but did not require achieving system-level changes from the outset. Nine studies ('no use') were designed to work at multiple levels among multiple agencies in an intervention setting, but the complexity of the system and relations between system elements was not articulated. We synthesised reported barriers and facilitators to scaling up, and how studies within each group conceptualised and used systems approaches, and methods, frameworks and principles for scaling up.

CONCLUSION

In physical activity research, and NCD prevention more broadly, the use of systems approaches in scale up remains in its infancy. For researchers, practitioners and policymakers wishing to adopt systems approaches to intervention implementation at scale, guidance is needed on how to communicate and operationalise systems approaches in research and in practice.

TRIAL REGISTRATION

PROSPERO (CRD42021287265).

Development of a core outcome set for school-based intervention studies on preventing childhood overweight and obesity: study protocol

INTRODUCTION

Prevention of childhood overweight is an important health priority. Evidence synthesis from studies evaluating school-based overweight preventive interventions is hampered by the wealth of different outcomes across studies. Therefore, consensus on a core set of outcomes for school-based overweight prevention studies is needed. This paper presents the protocol for the development of a core outcome set (COS) for school-based intervention studies aimed at childhood overweight prevention.

METHODS AND ANALYSIS

First, a scoping review will be performed to identify outcomes included in studies evaluating school-based overweight prevention interventions in 6-12 year-old children. Additionally, child focus groups will be organised in three countries to list the outcomes children consider important in school-based interventions. Next, an expert panel will identify all unique outcomes (eg, body composition) from the results of the scoping review and focus groups, ruling out how outcomes were defined and measured (eg, body mass index, body fat). In the next phase, a group of international stakeholders will participate in a Delphi study in which they will rate all unique outcomes on a 9-point Likert scale over three rounds to reach consensus on a COS. Participants will include healthcare professionals, policymakers, teachers, school leaders and parents of 6-12 year-olds. All rated outcomes will be presented to stakeholders in two online consensus meetings.

ETHICS AND DISSEMINATION

The Medical Ethics Committee of the VU Medical Center approved the child focus group study in the Netherlands (nr. 2020.071) and the Delphi study-including the consensus meeting (nr. 2022.0295). Other sites will obtain ethics approval for focus groups in their country. The University of Strathclyde School of Psychological Sciences ethics committee approved the Delphi study-including consensus meeting (nr. 72.27.04.2022 .A). The final COS will be disseminated through the diverse networks of all authors and participants.

TRIAL REGISTRATION NUMBER

This COS initiative is registered with the Core Outcome Measures in Effectiveness initiative (registration nr. 971).